1. Field of the Invention
The present invention relates generally to the field of dentistry, and particularly to a dental implant system for mini dental implants.
2. Description of the Related Art
Traditional removable partial dentures, i.e., the replacement of a relatively few missing teeth with prosthetic teeth, have been secured in the mouth by means of relatively rigid wire or other metal attachments extending from the dentures and removably attached to adjacent teeth. Removable full dentures, which replace all or nearly all of the mandibular or maxillary teeth, have traditionally been adhesively secured in the mouth. Single prosthetic teeth, i.e., crowns, traditionally require at least some portion of the natural tooth for fixed attachment thereto.
More recently, various implants have been developed that anchor directly into the mandibular or maxillary bone structure, with the prosthetic tooth or teeth being permanently or removably attached to the protruding abutment of the implant. Most such implants are relatively large and are not suitable for-the medically, financially, or anatomically compromised patient. The installation of such larger implants is a multi-step procedure, with the patient initially receiving oral surgery to open the gingival tissue and expose the underlying bone structure, whereupon the bone is drilled and tapped for the implant and the implant is installed. The patient must then wait for the soft tissue to heal and for a considerable period of time for the bone to grow around the implant and anchor the implant firmly in place. A subsequent visit is required after healing for the dentist to make an impression of the area in which the dental prosthesis is to be installed. The impression is then sent out to a dental laboratory for the manufacture of the dental prosthesis. Finally, the completed prosthetic tooth or other dental prosthesis is fit into place during still another visit to the dentist.
Even more recently, so-called “mini-implants” or mini dental implants have been developed. These relatively small implants do not require specific lying open of the gingival tissue or the drilling of relatively large holes in the bone structure. Rather, the small hole for the miniature implant can be drilled directly through the gingival tissue and into the underlying bone. The mini-implant can be placed or installed in most all compromised patients. This is a minimally invasive approach and even the medically compromised patient, and particularly the edentulous patient, can withstand the placement procedure due to the stability of the mini-implant and prosthesis. In cases where the procedure is for the reinstallation of a retrofit denture or prosthesis, the mini-implant(s) can be installed and the prosthesis installed thereon in a single visit to the dentist. In the case of a new denture, the mini-implant(s) are placed during one visit, and the impression for the prosthetic tooth or teeth is made during the same visit. The patient returns in only a few days later for the final fitting of the new prosthesis after it has been manufactured in the dental laboratory. As can be seen, the use of mini-implants greatly reduces the time and effort, and thus the cost, of implant placement, as well as greatly reducing the trauma to the patient.
However, many if not most such implants are of multiple piece construction, with a threaded implant portion having an upper end fitting generally flush with the exposed gingival surface and an abutment portion that attaches to the implant in some manner. Moreover, it has been recognized that some cushioning is desired between the removable dental prosthesis and the underlying abutment, implant, and bone structure, thus relieving the stress otherwise imposed upon the implant. This has been accomplished in the past by means of a small O-ring installed between the dental prosthesis and the abutment, which has proven to be less than satisfactory. In practice, these systems tend to collect food residue between the retainer cap and the spherical head of the abutment, thus preventing the ball of the abutment from seating completely and resulting in an unstable and poorly fitting dental prosthesis.
Another problem that can occur in the placement of conventional miniature implants is that the impression material if not contained may flow into the crevice between the gum line and the overlying structure. This can result in some chance that the impression material (or prosthesis material, in the case of a retrofit installation) may be locked around the abutment and its retentive mechanism, within the overlying interface between the gingival surface and the overlying protruding abutment.
Thus, a dental implant system solving the aforementioned problems is desired.